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AleksAgata [21]
3 years ago
11

X^2+18x+71 = 0 Solve the quadratic equation by completing the square.

Mathematics
1 answer:
SOVA2 [1]3 years ago
8 0

Answer:

x = sqrt(10) - 9 or x = -9 - sqrt(10)

Step-by-step explanation by completing the square:

Solve for x:

x^2 + 18 x + 71 = 0

Subtract 71 from both sides:

x^2 + 18 x = -71

Add 81 to both sides:

x^2 + 18 x + 81 = 10

Write the left hand side as a square:

(x + 9)^2 = 10

Take the square root of both sides:

x + 9 = sqrt(10) or x + 9 = -sqrt(10)

Subtract 9 from both sides:

x = sqrt(10) - 9 or x + 9 = -sqrt(10)

Subtract 9 from both sides:

Answer: x = sqrt(10) - 9 or x = -9 - sqrt(10)

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7 0
3 years ago
A new plasma-screen television has purchase price of 8590 if sales tax on this purchase is 773.10, find the sales tax rate
Nataly [62]

Answer:

9 %

Step-by-step explanation:

What % is 773.10 of $8,590?

X/100 = 773.10/8590 (x/100=is/of)

(733.10 * 100) / 8590

= 9

3 0
3 years ago
How many triangles exist with the given angle measures ?
Nonamiya [84]
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6 0
4 years ago
Ill give u ponits just help me out
zhannawk [14.2K]

Answer:

I can't really see because it's blurry but if you're solving for x then...

x=13

Step-by-step explanation:

77+90+x=180

167+x=180

-167 -167

x=13

7 0
3 years ago
Read 2 more answers
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The first proposal identifies total costs for materials and labor. The proposed charges add to ...
  410.20 +919.60 +9675.00 = 11,004.80
When divided by the number of seats (4250), the per-seat amount is computed to be
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The second proposal breaks out charges on a per-seat basis, so those can be added directly to give a per-seat total.
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The second proposal is about $2.60 -2.5894 = 1.06 ¢/seat more than the first.
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3 years ago
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